Expose IndexIterator and SlicesIterator on Bitmap

[tustvold]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

filter::SlicesIterator and filter::IndexIterator provide very efficient mechanisms to iterate through validity buffers, in some cases yielding order of magnitude improvements over element-wise iteration.

Describe the solution you'd like

Expose the following methods on Bitmap making use of these

fn iter_set_bits(&self, offset: usize) -> impl Iterator<usize> {}

fn iter_set_bit_ranges(&self, offset: usize) -> impl Iterator<(usize, usize)> {}

Describe alternatives you've considered

We could not do this

Additional context

#1802 tracks extending Bitmap with the ability to track an offset